Sennacherib would not have marched against Syria and Cilicia, nor Esarhaddon against Egypt; they would not and could not have left in the rear, in the most threatening proximity, the most dangerous enemy. If we nevertheless assume that during the sway of Sennacherib and Esarhaddon over Assyria the influence of Deioces steadily increased, we must concede to Herodotus that this higher position was gained not by martial deeds, but by craft and advice urging union. Then Phraortes, who, according to Herodotus, succeeded his father Deioces in the year 655 B.C., must have been able formally to assemble the tribes of the Medes round Bit Dayauku, and to organise them: it was he who united Media under his dominion. But we cannot place this union earlier than the period at which Assurbanipal destroyed Elam, and directed his arms against Arabia (p. 177): _i.e._ it must come after the year 645 B.C. Assurbanipal could not possibly employ his troops in repeated campaigns for the maintenance of Egypt, the reconquest of Babylon, the destruction of Elam, and the punishment of the Arabians, if a strong and compact force stood behind the passes of the Zagrus; still less could he look idly on while Phraortes subjugated the Persians, and then one nation after another in Asia, as Herodotus supposes, with the view of throwing himself on Assyria--if he could prevent it. The more probable course of events is, that Phraortes, as soon as he accomplished the union of the Median tribes, had to await and repel the attack of Assyria--that the tribes of the Persians among whom, precisely about this time, Achæmenes obtained the first place,[542] being threatened by the extension of the dominion of Assyria over Elam on their borders, combined with Phraortes for common defence, and consented to be led by the stronger nation. The tradition of the Medes, and their poems, on which the statements of Herodotus rest, would naturally antedate the liberation of their nation, and would place it in the times before Deioces; they would even ascribe conquests to Phraortes, and represent him as falling in an attack on Nineveh. It agrees with the position of affairs and the relation of the powers, that Phraortes should have fallen with the greater part of his army, as Herodotus says, in repulsing Assyria and Assurbanipal in the year 633 B.C. The first duty of his son Cyaxares must have been to avert from Media the consequences of the heavy defeat which destroyed his father. That Cyaxares, and not Phraortes, a century after the death of the latter, passed in the nation of the Medes as the founder of the Median supremacy, is clear from the fact that Phraortes, the head of the rebellion of the Medians against Darius, lays aside his proper name in order to call himself "Kshatrita, descendant of Cyaxares," and that at this time the leader of the Sagartians also gives himself out as a descendant of Cyaxares of Media.